Policy pathways for low-carbon transport in Ireland: Carbon taxes and ICE bans

This paper develops I3E-Transport, a new Irish passenger transport model that integrates behavioural, technological, and macroeconomic drivers to assess the effectiveness of carbon taxation and internal combustion engine (ICE) phase-out policies on emissions from private cars and public transport. The model is soft linked to the Ireland Environment-Energy-Economy (I3E) CGE framework, allowing for a comprehensive evaluation of how these policy measures influence transport demand, vehicle stock composition, energy consumption and emissions within the passenger transport sector. Simulations for 2024–2050 indicate that, under a business-as-usual scenario, emissions rise by 2050 despite modest gains in energy efficiency and alternative vehicle uptake. A carbon tax yields only limited abatement, whereas a comprehensive ICE ban from 2035—banning hybrids—reduces CO2 emissions by over five million tonnes relative to the baseline by 2050. However, the results show that the sector remains off track relative to implied carbon budget ceilings under a 2035 implementation, with only an earlier and comprehensive ban delivering substantial progress towards compliance, pointing to the need for timely and coordinated policy action to align Ireland’s transport sector with its long-term climate commitments.